if your intent is to attend pharmacy school and become a pharmacist, i would think this would confuse the admissions committee of your intent. math is really not used at all even though you have to be extremely proficient in algebra and be able to understand how calculus works. i'm not sure how any higher math classes would aid in pharmacy. i would think they would like to see a full time position in the pharmacy field (pharm tech, lab tech, something to do with bio or chem) while killing time after completing your first bs.
on the other hand, it is a personal choice. if you really want to pursue the math bs then i would go for it because you could find out that this is your true calling rather than pharmacy. however, like i said, if you're dead set on pharmacy then i would avoid the superfluous bs degree. lastly, if you just like being in school then maybe consider something more relevant to pharmacy other than math.
